A Body-Powered Wrist-Driven Supernumerary Robotic Finger

Area of Science:

• Biomedical Engineering
• Rehabilitation Technology
• Assistive Devices

Background:

• Grasping impairments significantly hinder daily activities due to reduced hand function.
• Current supernumerary robotic fingers (SRFs) are often limited by electronic components, leading to increased weight and power demands.
• A need exists for lightweight, practical, and cost-effective solutions for hand augmentation.

Purpose of the Study:

• To introduce the first body-powered wrist-driven supernumerary robotic finger (bpSRF) that eliminates electronic components.
• To provide a lightweight, affordable, and practical solution for enhancing grasping capabilities.
• To validate the usability and effectiveness of the bpSRF for individuals with motor impairments and for augmentation.

Main Methods:

• Designed and developed a novel body-powered wrist-driven SRF (bpSRF) primarily from 3D printed parts.
• Actuated the SRF using wrist movements, eliminating the need for electronic components.
• Conducted experimental validation with five healthy participants to assess learning curve and task performance.

Main Results:

• The bpSRF weighs only 52 g and is driven by wrist movements.
• Participants demonstrated high success rates and rapid learning of novel grasping patterns.
• The device offers a workspace volume approximately three times larger than a human thumb, expanding manipulation capabilities.

Conclusions:

• The bpSRF represents a significant advancement in assistive technology, offering a practical, cost-effective, and open-source solution.
• This design enhances grasping abilities for individuals with motor impairments and provides augmentation for healthy users.
• The body-powered approach overcomes limitations of traditional electronic SRFs, paving the way for new assistive devices.